Now Kenyan forces move to clear attackers from Nairobi's Westgate Mall once and for all. We'll bring you a live report.

Plus, diplomacy, dialogue and debate: world leaders step to the stage at the UN general assembly.

And a bid to take BlackBerry private. Should BlackBerry fans hold out hope for a RIM revival?

Now we are kicking off our extensive coverage of the UN general assembly this hour. But first, to the latest on the unfolding situation in Kenya. In the past two hours, sustained gunfire has erupted from inside the besieged Westgate Mall in Nairobi, explosions have been heard, tanks have been seen. Despite that, Kenyan authorities say that they have taken full control of the shopping mall. And they say that they will finish and punish the terrorists.

At least 62 people have been killed, but dozens are still missing.

Now it is still not clear how many hostages are still inside the mall.

Now CNN's Zain Verjee is on the scene. She joins us now live.

And Zain, again, there has been sustained gunfire there. What is the latest on this operation to clear out the attackers?

ZAIN VERJEE, CNN INTERNATIONAL CORRESPONDENT: There have been some explosions as well as some sporadic gunfire that has been ongoing for, I would say, the past couple of hours now.

What we just heard a few moments ago was some information from the Kenya defense forces. They are saying that they have casualties to report, three of them then are dead. It's not clear exactly what the scenario was or what happened, but that is the situation that they are reporting now.

A short while ago, the Kenya police had said that they were starting to diffuse explosives. Once source on the ground said that the bomb squad was in. We later saw a dog unit come by onto Pony Road and turn left. And halfway down the street, which is where -- excuse me, turned right, which is where Westgate is.

So we heard also the shots. And what we're discussing amongst ourselves as well as trying to get information from sources is that whether the gunshots are part of the clearing up, sweeping up activity that the military is talking about, or is it part of a firefight.

So there are a lot of -- a lot of -- there's a lot of confusion about the hostages. There's a lot of questions about the gunmen and about what exactly is happening inside Westgate now -- Kristie.

LU STOUT: Yeah, Zain, Kenyan authorities, they insist that they are in control of the operation, but as you just reported, they're suffering casualties, there's ongoing gunfire. We don't know the source of that gunfire. So is -- are authorities in control? Or what kind of help are they getting?

VERJEE: Well, authorities are consulting and working closely with a lot of international security and intelligence forces. The Israeli special forces are with the Kenyan military involved in this operation.

So what we're hearing is, is that the cordon -- there areas which have been cordoned off continue to get beefed up. And the helicopters -- actually one actually military police helicopter circling around here. And a small aircraft as well.

It's been a number of hours and we're still waiting to get information.

I spoke to two senior Kenyan officials that said that there were still militants in there and there were several, was the term that they used. Now that was a number of hours ago. We don't really know exactly what's happening in there.

And you know, most people watching this unfold, that have -- there are 65 people missing. So many Kenyans are looking for information about those missing and whether there are any hostages, if they're alive, if there's a casualty or body count. We're hearing nothing.

LU STOUT: You know, just now we were looking at live pictures of what appeared to be armed officials walking around the perimeter of the site.

Zain Verjee, thank you so much for that update there, giving us the very latest on the siege there in this upscale shopping center in Nairobi.

And very shortly, we'll be hearing from the Kenyan president Ohura Kenyatta who will be speaking on this Nairobi attack.

Now to other news, world leaders and protesters, they are converging right now on the United Nations. Now thousands are expected to gather as the 68th session of the UN general assembly gets underway.

And CNN is covering it live all week for you.

Now today, U.S. President Barack Obama and Iran's new President Hassan Rouhani share the UN spotlight.

In addition to those speeches, here is what else is on the agenda. Now the big focus this week will be the Syrian civil war. Members will likely debate a resolution on the Russia-U.S. deal to destroy Syria's chemical weapons and the Palestinian plan to push for full recognition in the United Nations.

Now last year, the UN upgraded their status to non-member state.

Now we will take you live to Iran's capital, Tehran, in just a moment. But first, let's go straight to the UN. Our senior international correspondent Nick Paton Walsh is there.

And Nick, we've got to talk first about Syria, after two years of war, is there finally a sense of urgency there at the UN to reach some sort of an agreement?

NICK PATON WALSH, CNN INTERNATIONAL CORRESPONDENT: I think no one realizes more how urgent it is necessary to get an agreement, but it still has been constantly held up.

We now have an additional road block for a body that was supposed to be implementing Syria's disarmament of chemical weapons under the convention they've just joined. There's a gridlock there. The Americans want that body to decide in the future whether or not Syria is in contravention of that convention. And the Russians want that decision to be made by the security council.

All eyes, really, on this afternoon's meeting between John Kerry and his Russian counterpart Sergei Lavrov to see if they can bridge that difference. And also if they can work out what text there could be of a UN resolution backing up what those two men have agreed in Geneva as well.

I understand from two diplomatic sources here the text of that resolution is still going to make some sort of reference to the important parts of the UN charter known as Chapter 7, which potentially in the eyes of some international lawyers authorizes force if such resolutions are not adhered to.

But they're going to have to water it down to keep the Russians happy. And everyone believes that resolution would require a subsequent vote in the event that Syria is in violation of the convention to decide what kind of measures would be used.

A lot on the table between those two men on a day where, as you know, we have both Barack Obama and Hassan Rouhani speaking here. The Obama speech likely to address Syria. Ongoing negotiations with Iran and generally the U.S. role in the Middle East, Kristie.

LU STOUT: Yeah, you know, it was just weeks ago when President Obama said that he was ready to bypass the UN security council and to strike Syria over its use of chemical weapons. He's also under fire for a variety of reasons, including NSA surveillance. Will he be under a lot of scrutiny when he gives that speech to the UNGA shortly?

WALSH: It is a remarkable day for him in many ways. So as you said, two weeks ago he considered this body to be paralyzed, this building to almost being consequential in the pursuit they had for some sort of punishment for the Syrian use of chemical weapons. That almost seems an age ago now, because Syria has joined the chemical weapons convention, has, despite saying publicly it wasn't necessarily going to agree with American deadlines, it has actually in fact delivered a declaration of its chemical weapons within the deadline that America and Russia set in Geneva.

So that process seems to be going on unilaterally in Damascus, while the diplomatic track certainly between Moscow and Washington is frozen here in many ways.

But there is a larger picture for Barack Obama here. And many accuse him of his Middle Eastern policy being somewhat in disarray because of the seemingly groping way that the Syria policies emerged in the past two to three weeks and of finding their way slowly as disagreements and a lack of alliances appeared around the world.

So I think many looking to this speech and to see what he can pull out of a hat here in the UNGA to see if he can set the White House's record there back on track.

A lot really also riding on whether or not he decides it's wise to meet the new Iranian president Hassan Rouhani. There's been no scheduled meeting. Both sides really holding it out as a possibility. But the window is short, because I think many think it may be unlikely he would choose to take that meeting before the important meeting of the permanent five members of the security council plus Germany who are meeting with Iran to discuss Iran's nuclear program and negotiations about that. He'll want to see how that meeting goes before he tries to potentially meet with Rouhani himself.

That kind of leaves Friday for that, really.

So a tight schedule and a lot riding on a lot of key choices here, Kristie.

LU STOUT: All right, Nick Paton Walsh reporting live for us from the UN. Thank you.

Now later, we'll take you live to Iran and to Brazil. And you can also find out more of our UNGA coverage on our website.

Now this article, it highlights the five things to watch as world leaders gather. You can find it, of course, at CNN.com.

Now you're watching News Stream. Later in the program, we will return to Nairobi. Where some of the survivors of the terror attack have told CNN's Arwa Damon of coming face to face with the gunmen. Stay with us.

(COMMERCIAL BREAK)

LU STOUT: Welcome back.

Now today is expected to be a pretty big day at the UN general assembly. The U.S. president will speak early followed later by the president of Iran.

Now in the past, that has been a real flashpoint. Two years ago, diplomats walked out when the Iranian president then lobbed a few verbal bombs at the west including the suggestion that 9/11 was an inside job.

But last year, about a third of the delegates did not show up for his speech. In fact, they boycotted out of protest.

But that was the old president, the anti-Israel president Mahmoud Ahmadinejad. And now, there is a new -- and it seems very different president -- Hassan Rouhani who tweeted a picture of himself from the back of his limo as he arrived in New York.

Many Iranians are optimistic about the change their new leader could bring to the country.

Now President Rouhani will address the UN general assembly late this afternoon. Reza Sayah joins us live from Iran's capital Tehran right now.

And Reza, what is President Rouhani likely to say?

REZA SAYAH, CNN INTERNATIONAL CORRESPONDENT: Well, I think he's going to talk about a lot of issues -- the nuclear program, U.S.-Iran relations, and Iran's relationship with the international community. But this is going to be a dramatic day at the UN general assembly, Kristie. I think much of Iran, in fact much of the world, is going to be eager to see if President Rouhani and President Obama will perhaps meet in the sidelines and shake hands. That, of course, will make history. Of course, these two countries have not had diplomatic relations for 34 years.

But what we've seen here in Iran has been remarkable. The optimism, the hope that these two countries will come together and break this deadlock that's lasted for more than three decades and establish some sort of relationship.

So you have a lot of optimism here. And as you mentioned, the man who sparked the optimism -- the new president Hassan Rouhani.

He's only been in office for roughly eight weeks. But consider all that he's achieved over these eight weeks. He's pushed for better relations with the U.S. He's become pen pals with President Obama, exchanging letters with him. He's released a number of prisoners that human rights groups consider political prisoners. And his office has tweeted happy new year to the world's Jewish community.

And it's this type of affective and aggressive charm offensive, if you will, Kristie, that has a lot of people here in Iran optimistic and hopeful that after more than three decades there's going to be some sort of relationship with the U.S. And again all eyes on both President Rouhani and Mr. Obama today to see if they've crossed paths. And if they do, what they'll do.

LU STOUT: So, from there inside Iran you're getting this sense of optimism about what is going to happen at the UNGA, what it will mean for the relationship. But what about resolving key critical issues point to dispute? I mean, for example, we know that Iran's foreign minister will be meeting his American counterpart John Kerry for talks on Thursday. That topic will be, of course, the nuclear standoff.

What kind of progress could be made on that issue at this point?

SAYAH: Well, Washington has long claimed that the big issue standing in the way of better relations is Iran's nuclear program. But the signals that Iranian leaders are sending is that perhaps their ready to make concessions. We don't know at this point what these concessions could possibly be, but we're hearing from sources here that perhaps Iran is willing to suspend enriching uranium at 20 percent, perhaps opening up some of their facilities, some of their military facilities to broader inspections.

But obviously any kind of fair deal you need something in return if you're going to give something. And what Iran wants, based on sources that we've talked to here, they want the U.S., Washington and western powers to respect and recognize this leadership. They want them to respect their right to enrich uranium and have a peaceful nuclear program. And they want some of those tough economic sanctions ease.

So it's a tough challenge, but again we're hearing a lot of optimism that there's lots of possibilities there. Of course, maybe the biggest obstacle is if these 34 years of mistrust that's built up. And I think a lot of people agree it's going to be challenging to break down that wall of distrust.

LU STOUT: Yeah, but a lot of hope, a lot of optimism to see this new Iran at the UNGA later today. Reza Sayah reporting live from Tehran for us. Thank you, Reza.

Now, this news just into us here at CNN. A powerful earthquake has rocked Pakistan. USGS says it's 7.8 magnitude, it's a big one.

Let's get the latest now with Mari Ramos. She joins us from the world weather center -- Mari.

MARI RAMOS, CNN INTERNATIONAL CORRESPONDENT: Kristie, this just happened in the last few minutes. And information is just now starting to come in of this earthquake striking in Balochistan region of Pakistan here to the south. This is the point right there from the USGS showing us where the epicenter of this quake actually happened.

Let's go ahead and zoom in a little bit closer. I want to show you the area that we're talking about.

This is not a densely populated area, as you can see, from this wider perspective. It's about 240 kilometers to the north-northwest of Karachi. There are reports in social media saying that it was felt in Karachi, and even as far away as New Delhi, some of that lighter shaking. But the earthquake itself, the epicenter, happens in this region here near Parwan (ph).

And 7.8, that's the revised magnitude from the U.S. Geological Survey. 69 kilometers north-northeast of Arwan (ph) in Pakistan.

One of the important things, not only is it a very strong earthquake at 7.8, there are -- there are areas here that are populated and we are looking at this area very carefully, because at 7.8 it is a strong quake. And as I understand it, it was relatively shallow at 15 kilometers deep.

We have Jana Pursley from the U.S. Geological Survey on the phone with us right now to tell us a little bit more about the information that we have on this quake. Thank you for joining us. What do you know about this earthquake so far, Jana Pursley?

JANA PURSLEY, USGS: Good morning.

It has been a very strong earthquake, a magnitude 7.8, just as you said. It has been felt in the Pakistan area. We don't have any information about damage, but as you said this is a shallow earthquake and potentially can be very damaging to structures nearby.

RAMOS: What kind of damage would you expect with a 7.8 quake, especially when we're talking about this region and the kind of buildings that they have?

PURSLEY: I would expect structures like adobes not very well -- earthquake prone buildings, they would suffer big damage from it.

RAMOS: When we talk about earthquake intensity and that's one of the important things, but also the depth is important. And in this case, we're talking about 15 kilometers in depth. Is that considered shallow for an earthquake?

PURSLEY: Yes. That is considered a shallow event.

RAMOS: Also as far as after shocks, I already see one after shock, that would be that red dot on the map that our viewers can see on our screen right over here. That is a new after shock reported also by the USGS. And that one 5.6. As far as aftershocks, what can we expect in this area?

PURSLEY: I would expect them for the next -- heavily for the next few hours. And they will last for days, possibly months.

RAMOS: One of the things that we were noticing when we started looking at where this earthquake happened is the type of terrain that we're talking about here. Not only do we have mountains, most of them relatively bare mountains, but also it appears that some of these communities are based in river beds, or sandy soils. Could that also have an effect on the kind of damage that we could see here?

PURSLEY: Certainly. As you may expect landslides and rock falls. Similar things we have seen in China from the large earthquake a few years back.

RAMOS: One of the reports that's coming in, people are saying that they felt this earthquake even as far away as New Delhi, which is about 1,000 kilometers away. Is that something that you would expect here? Or do you think the damage could be more widespread? Or do you think it would only be in the area closest to the epicenter?

PURSLEY: I would believe the damage would be confined to the area nearby the epicenter, however, as with the earthquake we had earlier this year, you will feel it very far -- you can feel it a lot farther away.

RAMOS: A lot farther away.

OK, is there anything else that we should be looking out for in the aftermath of this earthquake as we head through the next few hours? After all, you are the expert there from the U.S. Geological Survey after a 7.8.

PURSLEY: You might want to watch on our website. We'll be updating the information. And we may issue more information on the tectonics of the region.

RAMOS: OK, excellent. Thank you very much. That was Jana Pursley joining us from the U.S. Geological Survey in Boulder, Colorado telling us about the latest of this 7.8 earthquake that has struck in the Balochistan region of Pakistan. This is about 240 kilometers north and north-northwest of Karachi, a more densely populated area.

However, the area where the earthquake struck is dotted with smaller towns and villages across this region.

Kristie, let me go ahead and tell you a couple more things about earthquakes. When you talk about the damage of earthquakes, 7.9 you're talking about a major earthquake that would cause considerable damage as Jana Pursley was telling us right there on the phone. So that's definitely something we'll be talking about and paying attention to.

I want to reiterate that there are -- there is no information of damage or injuries that has come into CNN as of yet. But when you talk about an earthquake of this magnitude, an earthquake this large, this is definitely something that we want to be looking at.

Also, the terrain that -- where this happened, the type of housing of where this happened. And even the type of soil where it happened, this relatively shallow quake has the potential to cause significant damage across that region.

Also, these very large quakes, a 7.8, they're very rare. You only get about 15 of them per year. So that is why earthquakes like this area big deal. We will continue to monitor the situation, of course, and as news comes in of the 7.8 quake near -- in the Balochistan region of Pakistan, we will continue to monitor it as it comes in of course bring it to you.

LU STOUT: Yeah, Mari, as you say a 7.8 magnitude earthquake, it is huge, it is very rare, and yet an earthquake of similar magnitude did take place in the area, in southwest Iran and Pakistan in April earlier this year. And it caused extensive damage and casualties. So we will be keeping a close eye on the situation there in Balochistan. Thank you very much indeed for the update on this latest earthquake.

Yeah, Mari.

RAMOS: And Kristie, I'm sorry, just to add that's very important what you just said. With that earthquake, I remember when that happened. And one of the things is that we didn't get the information of the damage that had occurred until several hours later. And even days later, information was still coming in. With these very remote areas, it's hard to get the information right away when stuff like this happens. So that is very important point that this is an area prone to earthquakes and also prone to damage from earthquakes, because of the type of buildings that they have.

Back to you.

LU STOUT: Yeah. And the news will be rolling in in the hours ahead. Mari Ramos, thank you so much.

You're watching News Stream. And as world leaders gear up for the UN general assembly, Syria will be high on the agenda. We'll tell you what else to expect from the annual meeting next.

(COMMERCIAL BREAK)

LU STOUT: Coming to you live from Hong Kong, you're back watching News Stream.

As mentioned, the UN general assembly will spotlight the civil war in Syria. And the breaks are on international military action for now, but what do Syria's neighbors want to see done to stem the conflict?

Now the Turkish president spoke to CNN's Fareed Zakaria. Here is what he had to say.

(BEGIN VIDEO CLIP)

ABDULLAH GUL, TURKISH PRESIDENT: What's happening in Syria is having consequences that -- immediate consequences on Turkey, therefore Turkey is very active in this issue. And this should not be misunderstood that Turkey, wish war or Turkey wish to attack on Syria, that is not correct, you see.

What we want to see that this situation should not continue like this. If this continues like this, everything is going to backfire (ph).

FAREED ZAKARIA, CNN ANCHOR: But you want Assad gone. You...

GUL: We want -- we want a (inaudible) well calculated political solution for that.

(END VIDEO CLIP)

LU STOUT: All right, the Turkish president there.

Now President Gul is set to be the third speaker during the UN general assembly's morning session. The Syrian civil war likely to be one of his key topics. And our senior international correspondent Ivan Watson joins us now from Istanbul with more. And Ivan, what more can we expect from President Gul today?

IVAN WATSON, CNN INTERNATIONAL CORRESPONDENT: Well, I think it's very important from that interview with Fareed Zakaria that when asked does Turkey want basically Bashar al-Assad to step down, as has been spoken and explained many times in the past by the Turkish government, President Gul avoided saying that. That may be signaling a bit of a shift in Ankara's policy when it comes to Syria.

And recall just this month, Turkish war planes shot down a Syrian military helicopter after it strayed into Turkish territory.

The Turks may be trying to take a slightly different approach to Syria. And we may be hearing that in President Gul's speech, expected later today.

I spoke with one senior Turkish official earlier and he said that we're bringing reason back to Turkey's Syria policy. And this official also lamented the fact that Syria has effectively become a kind of battleground in a proxy war between Turkey and Iran, one of Turkey's neighbors.

It's worth noting that the Turkish president in statements to journalists a couple of days ago said, you know, you really can't move forward on Syria unless you talk to Iran. Again, that may signal another shift. And the Turkish president is expected to sit down with the new Iranian President Hassan Rouhani for a one-on-one meeting in New York on Wednesday. We'll see what comes out of that -- Kristie.

LU STOUT: Yeah, after two years of violence, no resolution. The eyes of the UN and the world are on Syria. What is the latest from there?

WATSON: Well, this also may be ties in with Turkish policy. In statements a couple of days ago, the Turkish president said that now one of the biggest concerns Turkey has is the radical groups that have grown in size and in influence, particularly in opposition held northern Syria. He said this was a big security threat to Turkey. And that's being really felt right now, not that a hard-line al Qaeda linked group called the Islamic State of Iraq and Syria is firmly in control of a strategic border town just about less than five minutes drive from the Turkish border, that's the town of Azaz.

Now this group, which is known by its acronym ISIS, it basically forcibly pushed out rebel Free Syrian Army units from that town a couple of days ago and have held on to it. And in the last 24 hours, this group came out with a statement saying that it had, quote, "cleansed Azaz of Syrian FSA rebels" and adding that they had to be cleaned out because they had made statements in favor of democracy, which this al Qaeda linked group said was against Islamic teachings.

It also accused the Syrian rebels of basically being traitors, because they had met with U.S. Senator John McCain when he made a brief surprise visit earlier this year to Syria to meet with these same Syrian rebels. And accused the rebels also of collaborating with western intelligence agencies.

These al Qaeda linked groups have grown more powerful, Kristie. And it does look like they're making a power play to push out the western and Turkish backed rebel groups that are increasingly, it seems, being eclipsed by hard-line al Qaeda groups on the ground in northern Syria -- Kristie.

LU STOUT: Ivan Watson there. Thank you very much indeed for that update.

Now up next right here on News Stream, we'll be taking you back live to Brazil, in fact. President Rousseff, she will be the first leader to take the podium at the UN general assembly today. Will she give a very public rebuke to Washington over the NSA surveillance scandal?

Also ahead, what a difference a decade makes. Once so popular, many called it the CrackBerry, BlackBerrry is now trying to save itself from extinction.

Now U.S. President Barack Obama and Iran's new President Hassan Rouhani are among the world leaders set to speak at the UN today. Now they're not scheduled to meet directly, but the U.S. and Iran appear open to the possibility.

The U.S. Secretary of State John Kerry and other senior diplomats will hold talks with Iran's foreign minister on Thursday.

A Russian state news agency says UN investigators are expected to return to Syria on Wednesday. (inaudible) says that they will continue investigating allegations that chemical weapons have been used not only in last month's attack near Damascus that killed hundreds of people.

Now a powerful earthquake has struck southeastern Pakistan. The U.S. Geological Survey says the quake measured 7.8 in magnitude. And the tremors lasted for two minutes. There are reports that some houses have fallen and been damaged, but there have been no reports of deaths so far. We are monitoring the situation. We'll bring you more details as they become available.

Now frequent, sporadic gunfire has been heard from Nairobi's Westgate mall. And CNN reporters, in fact, outside, they've been hearing explosions and shooting in the past few hours. Now Kenyan security officials say that they are close to ending the siege that now in day four.

Now, let's get an update on the situation there in Nairobi. Again, after four days, authorities say that they're closing in on the attackers who killed 62 people inside the shopping mall. Our senior international correspondent Arwa Damon joins us live from Nairobi. And Arwa, what is the latest on the operation?

DAMON: Well, the Kenyan authorities have been saying that they are in the final stages of fully clearing out the Westgate mall that is just down the street to the right here. Throughout the course of the day, we've been hearing small explosions followed by bursts of gunfire. Presumably that is as the Kenyan forces are going through trying to systematically clear out this location.

There had been previously potentially an unknown number of gunmen still inside. There have been great concerns that certain parts of the Westgate mall might in fact be booby trapped.

The Kenyan defense forces on their Twitter account saying that three of their soldiers died of injuries that they had sustained over the last few days.

And meanwhile, 65 people do remain missing or unaccounted for. A lot of people out there, Kristie, hoping for word of their loved ones.

The entire nation hoping that this horror that they have been through is going to end very, very soon, Kristie.

LU STOUT: Yeah, 62 people killed, 65 people remain unaccounted for.

And Arwa, for those who were able to make it out, the survivors, what are they telling you about the attack?

DAMON: They're stories are absolutely horrific, but we've also been hearing incredible stories of great heroism.

We did meet one couple that were a husband and wife team that are, in fact, radio presenters at one of the local stations here. The day of the attack, they were hosting a children's cooking show on the rooftop of the Westgate mall that was absolutely packed with kids.

(BEGIN VIDEO CLIP)

UNIDENTIFIED MALE: The kids were running around in their little aprons, chopping up.

We heard a series of gunshots. We called everyone to the corner -- all the kids and the moms and the parents and everyone. And we said get down, get down, get down on the floor. And just as we did that, the gunmen tossed a grenade to where we were.

A guy with the white shirt spoke first and he said, we're from Somali and we don't normally kill women and children. But then again you've killed our women and children. His colleague next to him...

UNIDENTIFIED FEMALE: Thin, tall, skinny face, black.

UNIDENTIFIED MALE: He just opened fire.

UNIDENTIFIED FEMALE: I got shot here. I had so much blood everywhere. I thought she was dead. And I was holding a dead baby.

(END VIDEO CLIP)

DAMON: Now, they managed to get out, because right after that happened, Alim (ph), the husband there stood up and began reciting a prayer from the Koran, and the gunmen, he says at that point after they believed that he was a Muslim, and he is a Muslim, decided to let them go.

Now Sima (ph), his wife, is not a Muslim, but she did make a point to tell us that even though she wasn't a Muslim, both her husband and their little daughter are and that she wanted to make sure that she brought her daughter believing in the true principles, she said, of Islam and that is a principle of peace, Kristie.

LU STOUT: Wow, an incredible escape for that family. Arwa Damon reporting live from Nairobi for us. Thank you.

Now we're also getting ready for the UN general assembly to begin. Secretary General Ban Ki-moon speaks less than 30 minutes from now. And the first country to follow is Brazil's President Dilma Rousseff and then U.s. President Barack Obama.

So there could be tension as relations between the U.S., Brazil and Iran have not been exactly smooth.

Now I'm joined now by Jim Acosta in New York and Shasta Darlington in Sao Paolo, Brazil. Let's go first to Jim Acosta. And Jim, what will President Obama say when he addresses the general assembly?

JIM ACOSTA, CNN CORRESPONDENT: Well, administration officials tell us, Kristie, that you should expect three big themes from President Obama and his speech to the UN general assembly. And in about an hour-and-a-half from now here in New York.

The first theme on Syria and its chemical weapons. The president will once again stress that while these diplomatic efforts are underway that the threat of forces still out there, at least in the minds of U.S. officials and so he'll be talking about that.

And then also what has really become the big story at the United Nations this week and that is Iran and its nuclear program and this possibility that the American president and the Iranian president may have some sort of face to face encounter at the UN. We won't hear the president talk about whether he's going to meet with Rouhani. But we will hear the president say that the pressure needs to be kept on Iran, on its nuclear program, that Iran has to be serious in terms of dealing with international concerns about that program. So we'll hear that from the president as well.

He's also going to touch on what administration officials describe as peace in the Middle East. That sounds great. What does that mean? He is going to be talking about setbacks to the Arab Spring, so you'll hear the president talk about that. And he'll also recognize the tragic events in Kenya that happened over the weekend.

As for that meeting, or potential meeting with President Rouhani, I am told by a senior administration official that at this point they feel like the White House is, quote, left the door open to a face-to-face encounter with Rouhani. It is now just really up to the days events to determine whether or not that historic meeting would happen, because no U.S. President has met with an Iranian president since the 1970s when Jimmy Carter last met with the Shah of Iran, that was of course before the Iran hostage crisis -- Kristie.

LU STOUT: Yeah, hi expectations for a handshake. If it happens, it will be a historic one. Jim Acosta there, thank you.

Let's go to our Shasta Darlington now who joins us live from Sao Paolo. And Shasta, when Brazil's president Dilma Rousseff takes to the stage and gives her address, will she raise concerns about the NSA's spying program?

SHASTA DARLINGTON, CNN INTERNATIONAL CORRESPONDENT: Well, Kristie, that's what we expect. And in some ways it's unfortunate with all of the conflicted relationships in the world these two countries are supposed to be allies. And as recently as May, in fact, leaders from both Brazil and the United States were talking about a new era of bilateral relations, that was when Vice President Joe Biden was in town.

But things turned sour very quickly when documents started to leak from Edward Snowden.

(BEGIN VIDEOTAPE)

DARLINGTON: At the United Nations, they'll likely hear more bold words and sharp rebukes from Latin America's economic powerhouse. Brazilian President Dilma Rousseff will be the first leader to take the podium when the general debate opens on Tuesday. Her expected focus outrage over reports the United States was spying on her communications.

Rousseff's speech comes a week after Brazil and the United States agreed to postpone an official state visit to Washington, the first such visit for a Brazilian president in almost two decades.

Washington played down the decision.

JAY CARNEY, WHITE HOUSE PRESS SECRETARY: And the president made clear that he is committed to working together with President Rousseff and her government to move beyond this issue as a source of tension in our relationship. As a broad matter, obviously this country collects intelligence, as do most countries.

DARLINGTON: But in its statement, Brazil was much more critical, saying the illegal interception of communications constituted an attack on national sovereignty.

The problem started when Brazil's TV Globo (ph) aired a series of reports based on documents leaked by Edward Snowden alleging the National Security Agency spied on the emails and cellphone communications of Rousseff, her top advisers, and even Brazilian companies.

President Obama tried to patch things up on the sidelines of the G20 meeting and during a last minute phone call. But the two sides finally agreed the state visit wasn't going to happen.

In announcing the postponement, the U.S. said it had previously ordered a thorough review of American intelligence activities, but acknowledged that process would take several months.

Reaction to the fallout has been mixed here in Brazil.

"We aren't at war. We didn't do anything to deserve spying. So I think the president did the right thing," she says.

"I thought it was a huge lack of respect. We have a right to our privacy," she says. "But I don't think she should have canceled the trip."

(END VIDEOTAPE)

DARLINGTON: Now, for its part, Brazil has come up with some costly ideas for how to isolate its communication from prying eyes and prying ears. On the one hand, it wants to require internet companies like Facebook and Google to build data centers right here in Brazil so they wouldn't be as vulnerable.

And on the other hand they're talking about building a new submarine cable that would bypass the United States. This would cost a lot of money. And you can imagine companies are putting up a lot of resistance, Kristie.

And due tune in to CNN for special coverage of the UN general assembly. We'll bring you the opening remarks and some speeches by member states. Remember, it all starts in the next hour. In the meantime, we've got more News Stream after the break.

(COMMERCIAL BREAK)

LU STOUT: Welcome back.

Now this week on Leading Women, we return to our profile of Dr. Helene Gayle. As the head of CARE USA, she oversees one of the largest NGOs in the world. An Gayle tells Isha Sesay why taking risks with her career has helped her to reach the top.

(BEGIN VIDEOTAPE)

HELENE GAYLE, PRESIDENT, CARE USA: Every year, they award the Desmond Tutu award. And I was the honoree in 2009. And that was my first picture with Nelson Mandela.

ISHA SESAY, CNN INTERNATIONAL CORRESPONDENT: As president and CEO of CARE USA since 2006, Helene Gayle has seen her share of humanitarian crises whether caused by conflict or natural disasters.

Gayle has a particular soft spot for children. She started a career as a pediatrician and later spent 20 years with the Centers for Disease Control in Atlanta.

She left in 2001 for a director role at the Bill and Melinda Gates Foundation in Seattle. The Gates Foundation is a CARE donor.

GAYLE: When I left CDC, I was running one of the largest centers within CDC, focusing on HIV and other related diseases. Going to the Bill and Melinda Gates Foundation was a fabulous experience. When I went, it was early in the days of that foundation, but you know, it is now the largest philanthropic organization in the world.

Each time I've made those moves, it's been scary. It's been a bit of a risk. It's been kind of zigging when I could have zagged or not a straight line path. But each time, you know, I feel like I've gained a lot as a professional, I've gained a lot personally, but I've also gained -- I felt like I've been able to give back even more.

SESAY: That commitment to family, giving back and her work ethic, she says, come from her upbringing. The family owned a beauty supply store in Buffalo, New York where Gayle and her four siblings pitched in to help.

GAYLE: It was fun. It was enjoyable. You know, I think it taught us a lot about integrity.

My father was kind of the more soft, kind-hearted, my mother was the brilliant, analytic force of nature.

One of the things she used to tell us all the time was to use our voices and to speak up. She'd say you've got a good brain, you've got a big mouth. Use it.

So she really encouraged us to take risks in life and kind of grab life by the horns.

SESAY: Your mother suffered from mental illness. And I just wonder what -- how that has shaped you and the journey you've taken?

GAYLE: I think it gave me a sense of compassion for people who are marginalized, who are stigmatized. And so you know I hope I pass that on by the way I treat other people in the way that we do our work here at CARE.

SESAY: We were there in Atlanta as CARE celebrated its 67th birthday and Gayle spoke to staff.

GAYLE: 67 incredible years of service, a real legacy that we are all a part of.

We always say at CARE that we would love to see if we can work ourselves out of business.

(END VIDEOTAPE)

LU STOUT: Helene Gayle there.

Now you are watching News Stream. And still ahead, it has been a long fall from the top for the once dominant BlackBerry device, but has a white knight come to the rescue for the smartphone company?

We'll tell you after the break.

(COMMERCIAL BREAK)

LU STOUT: Welcome back.

And now Apple and BlackBerry, just the numbers tell the story.

Consider this, over the weekend Apple sold 9 million of its new iPhones. It did better in three days than BlackBerry did for the entire last quarter. BlackBerry sold just 5.9 million smartphones during the last three months.

And by the way, BlackBerry has tentatively agreed to a $4.7 billion takeover bid.

Now, who is this white knight that may help BlackBerry fight of imminent fiscal ruin? Well, the Canadian insurance company Fairfax Financial is the one making that multibillion dollar offer.

As Richard Quest now reports, it has been a long fall for the company that helped create the smartphone business.

(BEGIN VIDEOTAPE)

RICHARD QUEST, CNN INTERNATIONAL CORRESPONDENT: It was the essential device for the titans of global business and politics, the once mighty BlackBerry. Even President Barack Obama vowed to hang on to his at all costs before taking office in 2009.

BARACK OBAMA, PRESIDENT OF THE UNITED STATES: I'm still clinging to my BlackBerry, they're going to pry it out of my hands.

QUEST: At its height, BlackBerry held a commanding 47 percent of the U.S. market. That has collapsed to just over 2 percent today.

At its peak, BlackBerry had a stockmarket value of $55 billion. Today, its market value is under 10 percent of that.

The collapse of BlackBerry has been stunning. The device maker was outdone by the likes of iPhones and Android, devices marketed directly to consumers who loved their sleek design and user friendly apps.

PAUL LAMONICA, CNNMONEY.COM: Once you got to the level that iPhones and Android devices were something that people were bringing into work and not just using as, you know, a personal device, that was really the death knell for BlackBerry. Once it became clear that BlackBerry was not going to keep that strangle hold on the corporate and government market, it just became very difficult for BlackBerry to stay relevant.

QUEST: In a last effort to save the business earlier this year, BlackBerry unveiled two much delayed smartphones and a top to bottom overhaul of its operating system.

The CEO Thorsten Heins touted the phones as a new beginning.

THORSTEN HEINS, CEO, BLACKBERRY: This is one of the biggest launches in our industry. And today is actually not the finishline, it's the starting line.

QUEST: The phones got good reviews. Their fate can be summed up as too little, too late. Sales were dismal. The latest billion dollar quarterly loss is largely because of unsold phones.

And now, BlackBerry has announced it's entered into a preliminary agreement to become private.

Even if this deal is done, the company faces almost insurmountable challenges.

LAMONICA: It's no longer in the glare of investors who are clearly impatient with the company's lack of a real strong strategy. But that being said, they're still burning cash, they're losing sales, marketshare is going down. None of that changes if they go private. All that changes is we don't get to see on a daily basis the stock sliding.

QUEST: BlackBerry's days as a public company may be over. It's struggle to stay alive just goes on and on.

Richard Quest, CNN, New York.

(END VIDEOTAPE)

LU STOUT: Now, our special coverage of the UN general assembly is about to kick off. Richard Roth is our senior UN correspondent. He's with Isha Sesay at the UN. Hello there.

And Richard, the UNGA, it's been called a spectacle of diplomacy and dialogue and debate. But behind the scenes, what's it really like to be there and to cover it?

RICHARD ROTH, CNN CORRESPONDENT: Well, journalists will tell you it's a grind, but I think there's some anticipation this year, because of the possibility of a handshake or an acknowledgement between the United States leader Barack Obama and the new Iranian president, which if it happens it'll happen today here and it may not be in sight of cameras. It may be - - there are several possible opportunities.

And also there's the ongoing Syria crisis, which provides for media covering this, and for any diplomat some urgency.

And of course there's a host of other issues that tend to never get solved in four days when you put 170 leaders in one building.

LU STOUT: You know, and the question about the handshake, everyone is buzzing about the anticipate it, it could happen -- handshake between the U.S. President Barack Obama and the Iranian President Rouhani. You know, if and when it happens, are the reporters all primed at the ready with their cameras to get that moment on camera?

SESAY: I think it's unlikely that the reporters will be there, only if we get a tipoff which we don't anticipate at this stage.

ROTH: I think you can focus on the annual heads of state, heads of government luncheon, which takes place where we are told the Iranians are supposed to be there. Sometimes they'd boycott it in the past, because alcohol was going to be served. Barack Obama left last year without the lunch because he was campaigning.

There could be, depending on how high profile Washington wants to make it, an actual handshake across a table at the luncheon. It provides a neutral opportunity on a world setting.

But you know...

SESAY: No -- I mean, you don't know. And you've got to put it in context, I mean, this is a big deal if this does happen. I mean, it would be the first time since 1979 that the presidents of these two countries have had a face-to-face.

So it's a big deal. We're all watching anxiously to see if it happens, Kristie.